Module persist 

R-tree checkpoint/restore for durable persistence.

On-disk framing

Plaintext R-tree checkpoints start with the 6-byte magic RKSPT\0. The first 4 bytes are never SEGV, so detection is unambiguous.

Encrypted checkpoints use the same SEGV framing as the vector engine:

[SEGV (4B)] [version_u16_le (2B)] [cipher_alg_u8 (1B)] [kid_u8 (1B)]
[epoch (4B)] [reserved (4B)] [AES-256-GCM ciphertext of the inner payload]

The inner payload is either the raw rkyv bytes for R-tree or the msgpack bytes for geohash — the existing plaintext format. The nonce is (epoch, lsn=0), and the 16-byte preamble is used as AAD.

Storage key scheme (in redb under Namespace::Spatial):

• {collection}\x00{field}\x00rtree → serialized R-tree entries
• {collection}\x00{field}\x00meta → SpatialIndexMeta

Structs

SpatialIndexMeta

Metadata for a persisted spatial index.

Enums

RTreeCheckpointError

Errors during R-tree checkpoint operations.

SpatialIndexType

Type of spatial index.

Constants

RTREE_FORMAT_VERSION

Current format version for rkyv-serialized R-tree snapshots.

Functions

deserialize_meta

Deserialize index metadata from bytes.

meta_storage_key

Build the storage key for spatial index metadata.

rtree_storage_key

Build the storage key for an R-tree checkpoint.

serialize_meta

Serialize index metadata to bytes.